We've finally moved beyond Jack's (Milo Ventimiglia) death on This Is Us, and we'll learn even more about the Pearson patriarch in this week's episode.

In newly-released photos for the October 16 episode "Vietnam," fans get their first glimpse at Jack's younger brother Nicky, played by Michael Angarano(Will &Grace, I'm Dying Up Here). We'll also hear the tragic story of how Jack lost his brother in the war, and how that transformed him into the person he was when he met Rebecca (Mandy Moore).

Click through the sneak peek images above, and don't miss the all-new episode on Tuesday.